Sadly, these ad discrepancies are a big part of the world we live in today. Companies are so big and far flung that often the right-hand doesn't know what the left-hand is doing.
Further, many of the ad campaigns are run by extra aggressive marketing and advertising units which are not in touch with the rest of the company, indeed, often are not even part of the company but just a hired consultant. Try calling one of the promotional 800 numbers and tell them you have two-party service or a 'local battery line' and if you can still ger DSL and they'll say "sure you can, that's not a problem". They're just a bunch of boiler room serfs under heavy pressure to sign up as many names as possible. This isn't just the phone companies, but big banks, department stores, even hospitals.
Everybody's situation is different.
For myself, I found it cost effective to switch to unlimited LD. The reason was that while I make extremely few traditional "long distance" calls, I make a lot of local toll calls. Local toll rates are high as is unlimited regional local service (which is what I had before). Upgrading to unlimited national LD from regional LD is only a few bucks more.
In the old days of the Bell System short distance toll calls were very cheap, only a few cents per minute. But after divesture every toll call, whether 10 miles or 1,000 miles away became the same rate. For myself, I was paying EIGHT times as much for my LD calling. So much for divesture saving us ordinary consumers money.
I think the new era phone companies new most subscribers area of interest was regional toll calls, not 1,000 long distance. Thus, it was profitable for them to lower the price of 3,000 mile calls while steeply increasing 10 mile calls.
Very good and important questions to ask. A common practice today is to have promotional plans to lock you in, than later discretely steeply jack up the cost of service. Most consumers will be lazy and do nothing and keep the service. Another practice, esp in long distance, was to discontinue a plan and revert to higher a la carte pricing. A third practice was to add a service charge on top of actual usage charges. I avoided many LD plans that add a $5/month service charge since that $5 far outweighed any savings from the plan.
I will note that my Verizon LD plan has been fixed and trouble free since I got it. Having unlimited service does make it more pleasant to chat on the phone without worrying about the meter running or wasting calls to someone's machine and playing phone tag.
My LD plan has no tie-in to DSL. However, getting DSL does have tie-ins to other services. One must be careful ordering DSL, although users I've spoken to are very happy with it. I'll probably go that way when I get a new computer than can handle the speed.
It has been fairly recent that the local telcos have been allowed to offer their own long distance service and bundle it with other offerings.
Many parts of telephone service are no longer offered as "common carrier" status, that is, they have been deregulated. I think nowadays basically the local dial-tone line is all that's left of common carrier regulated status, everything else is optional and unregulated. The phone co can thus introduce or withdraw services and pricing as it sees fit. I pay a single phone bill to Verizon, but on the fine print (literally) of the bill are a variety of Verizon subsidiary companies offering various services to me, all bundled together.
If I fail to pay my phone bill, Verizon can shut off instantly any of the optional services. However, it must follow PUC procedures for protecting local service. The bill includes a complex matrix of charge and payment allocation.
That's really only the fair to go nowadays since the competition has the ability to market as it chooses, so the local Baby Bell should be able to do the same.
Those who advocated free market competition in telephone service had a false idea that prices would be the lowest possible. That is not how it works in other businesses. Every business has some high profit items and low-profit items for a variety of reasons. Sometimes it's more profitable for a business to charge a high markup and sell low volume.
The sad fact is that our telephone companies, once proudly quite staid and proper, are now as slippery as the guy in the loud plaid jacket at the used-car lot down the street. In the old days, when Ernestine quoted you $4.65 for local service, that is what it cost you. Today the quotes are meaningless with all the extra "FCC Line Cost", "Deaf Relay Service", "911 Fee", "Porta number fee", "Help the Martian settlers fee", etc.
I know others steadfastly maintain long distance rates are lower on account of competition. However I maintain it is technology. Cheap switchgear and fibre channels are a world of difference to what AT&T had to do to offer long distance 30 years ago. Rates were dropping long before divesture came along. Further, many toll call services, such as collect and pay phone, have gone up dramatically. Remember that the same technology that allows you to buy a computer for $500 that once not long ago cost $10,000 applies to telco equipment as well.
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