Yes, Hattrick has 41 seasons, and still not fallen apart, despite them not adjusting salaries every season. How strange that is.
I'm very sure that when the game first started they did make adjustments to their formula's.
Lets just see a quick summary of Hattrick
Season 11 is when the current version of HT was born, ending the test runs of HT classic.
Season 12 is when they added Promotion and relegation.
Season 15 there was a "depression" resulting the the developers resorting to give out 200k to each team to boost the economy
Season 21 HT crashes completely and has to be restored from a backup
Season 29 second crash
Season 30 added skill decline
Season 38 Transfer Market Regulation
The point being that until season 12ish HT was crappier than BB was at release. They have made changes the entire time to adjust to what they see just like BB does. The BB's have looked to take what good they can from HT that they think will work here and integrate it into the game. They do their best do regulate and adjust BB so it does not stagnate in the same manner that HT has.