For me, it was missing a purpose to actually spend all this money you accumulated in the game. You'd complete missions, get paid, and you could buy more weapons, but what was the point if the weapons dropped by enemies would suffice? In San Andreas, Vice City, and Vice City Stories there was a bit to spend money on--although in VC it got to a point where you were constantly generating money from businesses with no threat of losing income, the same with San Andreas. VC Stories was the perfect balance as you could buy businesses like in Vice City, but you also had to defend your properties like in SA.
I found The Lost and Damned to be more enjoyable than the main story. On my complaints about what was lacking from GTA IV I've come to the conclusion that it was a different route to the American dream than in other GTA games. Claude was just...dropped into Liberty City after escaping. Tommy was in VC originally on business and just got...sucked in basically and rose to power. Victor kind of fell in with shadiness since he had nothing else going for him in VC, plus his troublesome brother appeared, etc.
Niko's American dream wasn't meant to be criminal. It was like CJ's. He just popped up to see family and see what was going on and in Niko's case, what opportunities were available--then BAM! Crooked people everywhere. Niko actually wanted a legit life and stuff, so his intent wasn't to accumulate money and have a big boss lifestyle, really. That's the conclusion I came to.
...because honestly, the money you racked up in GTA IV, by the middle of the game Niko could've said "F*** this, I have enough to be more than comfortable for years if I live modestly."
