Currently teams are spending huge amounts of money because things are good.
They commit to giving players big, long term deals because TV money is sustaining them right now.
I think it is unlikely that TV money will continue at that level indefinitely and then a lot of teams (read midtable sides paying players 50,000+ per week) will have to sell their top earners or go bust.
Look at Leeds, they were assuming they would keep getting into the CL, but they didn't and they collapsed. It is entirely possible that the same could happen to another team that has budgeted for CL/Premiership money to miss on on them and finish up in major trouble.
The next Premiership TV deal is up for negotiation quite soon, I believe. It will be interesting to see how it compares to the current one.
Take Rangers for example. They failed to qualify fo European football this season, having budgeted for it, and were desperately trying to lower their wage bill through January.