Speevy,
You sound like either a disgruntled ex-employee or student of one of the OAT associates.
The important consideration in this case is that Arizona, specifically the Phoenix area, enjoys a good climate for VFR flight training. This has been demonstrated over many years - indeed OAT has had associations with the region for some time. The U.S. offers undeniable advantages over E.U. in terms of tax and currency exchange; hence it makes sense to locate a fair weather base in a place where the weather is good VFR and costs are potentially less.
I have flown out of Scottsdale myself and found the area excellent and weather very good. In addition to plenty of attractions,aside from flying, the locals are enthusiastic and very welcoming.