I don't think Eng-Tips promotes laziness. I read/write during my lunch break, not on the clock. It may not be the equivilent of getting a FE or PE Exam practice book and working out problems on lunch, but it gets at some issues that aren't in the textbooks.
I find many posts to be questions for clarification, interpetation, or a depth beyond what the textbook, manuals, and similar resources often cover. I know a while back there was a discussion about if it made any sense to have a split lockwasher with a flat washer underneath. That's not something that is typically discussed in a textbook. I've also seen questions such as "What has anybody used for the capture velocity of exhaust fumes in ventilation?" Typically, I presume that the posters has a knowledge of how to design ductwork and such, but there is a piece of information missing. Yes, there are books that give a typical value, but how much is that trusted? The extra piece that another individual might be able to offer such as, "(Insert reference) states a velocity of 2000fpm, but in a particular project I had I used this value and it didn't seem to be sufficient. We had to increase the fan speed and I'd figure the velocity was at 2500fpm when we were satisfied."
Typically it seems the most interesting and the best response come when somebody has interpetation or there is a vague area in the data. I don't often see people asking for a "do it for me" response. Drawing on others experience and/or mistakes is not lazy, it's smart. Eng-Tips is just another watercooler for us to gather around and discuss.
Another type of post that I see is a rant or somebody asking for advice on what to do in a particular situation. I don't have any psychology or social interaction texts, and don't think I'd trust them if I did. Again, Eng-Tips offers a place to discuss the issue and (for myself at least) assure individuals that many engineers will have issues with customers/bosses/vendors at some point and it's no big deal.
-- MechEng2005