It's a shame all crew aren't in the same hotel. It's almost like BA were trying to drive a wedge in crew relations

On a more general level, a sense of entitlement with certain types of role within an organisation (among some people only; not all), happens across many industries. It's the case in healthcare with Doctors; it happens in financial services with people in sales/trading/front office roles, versus those who work in Operations. Doesn't make it right, but it happens.
This is probably more for Ask the Staffer, but I'm assuming that, aside from these discrepancies, IAG crew will generally be put up in the same hotel, if BA and IB are serving the same destination?