Well, there are a lot of non-paying programs out there, but I will mention that sometimes your emails aren't ignored, they are eaten by a bad server, or whatever. Er, not repeatedly, but SOMEtimes...

Or there are WM like me who start out with all these idealistic terms then end up whittling it all down to a one-legged chihuahua hobbled to a bowling ball type business plan... I pay as funds are available and put it on my site... people still get angry or expect me to pay them out of turn just because they email me or make a stink.
I do not delete them for that, I wish I could, but I am not like that. My site does occasionally eat accounts when the server has problems - it's always done that and the programmer always denied it - so maybe that is what happens with you all sometimes too. I know I lost my Paradise Hits account right after redeeming several hundred paradise bucks... But this stuff happens, you know??
I think you really have to look at the personality and professionalism of the program owner. (Yes, I can spell professionalism, sheesh! Don't think I don't know what it is, I just have too hot of a temper to really stick to my professionalism type resolutions and all that). Take lgwong - he's one of the most professional program owners I know. So is Cynthia of Letterwealth. I trust them both. Others are in-between on the whole thing, their humanity is a bit more uh, volcanic in nature. Then there are others, who basically couldn't conceive of behaving as they would like to be treated and ought to be dragged behind a darned skeered horse across a field of goatheads.
On the subject of Tasia's - that program grew incredibly quickly and everyone needs to just take a step back from being angry at not being paid. I was angry too, but after talking with Amy, I apologized and am going to wait to see what all happens. They are doing their best.