AbigailII: Speaking of the buy in - it can be important on the no limit page.

That is for example, the 250 buy in on the no limit page. So if I'm playing and someone else has 2000 chips and goes "all in" - if I only came to the table with 250, I know I can call (up to my 250) and know I will lose no more then that - if I had come into the table with 2000 chips, I may not want to take the chance for that many chips.

As for the profile page - I believe if you are below a certain amount of chips, on your profile page will be an option to get more chips. But you won't see that unless you get that low I believe. (have not seen it myself yet.)