Of course, not every CSR reads the contract text, so you may need to speak to the right person.
Not the case for phones, though.
I had a home phone and a backup prepaid cell, so eh, nothing to lose.
I've never tried to start service with VZW, T-Mobile, or Sprint, so I don't know what information you get up front with them, but with any US cell provider, you still get a trial period during which, if you decide that the service is no good where you live/work/hang out, you can return the phone, cancel, and depending on how soon into your service you are, pay nothing, or a partial month plus activation fees.
AT&T's policy is if you return by the third day, you only pay for each day of service you had, and your activation fees get refunded.
Anyway, I started service with AT&T after learning how over 90% of all persistent dropped call issues on AT&T involve some model of iPhone.
If it were the network, then it would be every phone, no? So I bought a BlackBerry Curve 8900, and I've had three dropped calls in 19 months.
People frequently drop their iPhone in a mug of beer (HOW?!), or jump in the pool, or some other stupid way of destroying it, then put their SIM card in a basic phone. Then they have a store or customer support remove their unlimited data because oh it's soooo expensive, then expect to get it put back on well after it was announced that the only way to get it back was to never voluntarily remove it. If you already have a smartphone or iPhone unlimited data feature, you are more than welcome to keep it if you upgrade or simply swap phones to another smartphone or iPhone.
If it was removed because someone at Walmart bungled an upgrade or something similar, it can be restored, just don't wait six months to call in about it.
Now, maybe Verizon doesn't know, but some of the heavy abusers of cellular data with iPhones use upwards of 40-50 GB per month. You're not going to use that much data browsing the web, but with a jailbroken iPhone, you can get a 7 to 14 megabit connection shared with a whole network of computers for all of $30 per month... and that is spelled out as abuse of the service in the ToS, which is written in very basic English.
I assume that unlimited data will be revoked again once LTE rolls out, or it will be exclusive to the first iteration of CDMA iPhone.
FYI, the only data services available for the original iPhone are all unlimited data, with varying amounts of SMS message allotments. Wink wink, nudge nudge, say no more.
"Mr. Spock succumbs to a powerful mating urge and nearly kills Captain Kirk." -- TV Guide, describing the Star Trek episode _Amok_Time_