Well if you based it on surveys, I would probably rarely be able to do scratch off. I'm one of the people that stops by most days & does the scratch off. However, I RARELY qualify for the surveys--I think I have qualified (and completed) 4 since I joined in early November. I look at the scratch off as a consolation prize since I TRY to complete the surveys, but usually don't qualify.

I have done a fair bit of shopping, though, so maybe you need to have one qualifying transaction in a certain time period (weekly or monthly would be fair) to be able to get the scratch off.