If you go down this road, exactly which address blocks an organisation gets from ARIN will prohibit them from getting a /22 from RIPE NCC? And if you look at organisational structure it becomes even more complicated: what if a big corporation has subsidiaries in both the US and EU, and the US company gets address space from ARIN. Does that disqualify the EU company/LIR from getting address space?
Remember: someone has to be able to implement the policies we create here! :)