When it comes to unlimited plans, people really seem to be foolish. Why in the world would you pay full price for a phone just to keep the unlimited plan? Is it because you are using 50 GB per month, or is it because you lay awake at night worrying about how much data you have left on your plan?
The 4 GB share everything plan is $70. The 10 GB plan is $100. That's $30 per month more if you were to use 10 GB, which I doubt people are using. That's $360 per year more *IF* you really use 10 GB of data.
So you would rather pay full price (an extra $450) just so you can march around bragging about unlimited data? Seems just pound foolish to me....
Why do it? I don't think it's a matter of bragging at all; rather, it depends on your financial situation. I'm paying about $80 a month for everything: talk, text, and unlimited data (I get a 15% discount per month on my plan). You said the 4 GB share everything plan (for use with a smartphone) is $70, but you're forgetting the $40 "monthly line access" for the phone, which brings the monthly cost up to $110. For people who don't have to worry about paying more per month, that's fine, but for people who are looking to cut monthly costs, it makes more sense to pay more upfront and save monthly. Here's my personal math:
-$110/mo. x 24 mo (new contract) + $212 (new phone including tax) = $2852 over 2 years
-$80/mo x 24 mo (for comparison's sake) + $688 (new phone including tax) = $2608 over 2 years
The savings would be over $200 over 24 months. Sure, that doesn't add up to much per month, but savings are savings, right? Like I said, actual mileage may vary for each person.