I have to say - why did you give them your cell number? When signing up for _anything_ online - only give them information you want them to have. They have no need for your number, and thus shouldn't have it.
Besides - looking at that screenshot it is pretty clear that it is a crappy advertisement with nothing to do with photobucket. You don't click on pop-ups do you?
I don't mean to harsh but you should have sirens going off immediately if are ever told you could "win" something online - especially if it asks for _any_ type of information about you.
If you really are that upset with photobucket then send them an e-mail explaining how you feel their acceptance of a scammish advertisement upset you.
I don't have a good answer to your post -- I dodge scams and phishing attempts all day long. This one just caught me with my guard down.
I only wanted to make others aware of the possible cost of giving them the cell number. I was aware I might have to deal with a few unwanted text messages at 15 cents each, but the premium bullsh^t just floored me.
There are plenty of free photo sites out there without all this annoyance.
Flickr is one of them.