There are plenty of cases where it just wouldn't make sense to switch after looking at the costs, opportunity costs, etc. For example, if his site makes him $10 a month, outages cost him $1 a month that could be mitigated by moving, and it would cost $1000 of labor to swap providers. (Depends on interest rates.)

Perhaps it was originally a failure to not have a plan to easily move from a provider, but it doesn't seem unreasonable to me that right now it may cost too many hours of work to justify the move.