It makes sense that they are doing that.  IIS doesn't behave well over the
"weeks at a time" timeframe and needs to be restarted.  Likewise for Windows
itself. (Any good admin is patching the server too, and some of those
require reboots.)

Though, several times a day is excessive.  If I were that host, I'd be
leaning on or kicking out the clients that were causing problems with their
code rather than just putting up with it and causing problems for other
clients.  You can restart individual virtual webs separately... but wether
or not that will fix their problems depends on the problem.

So, the frequency of occurance is NOT standard.  That they are doing it at
all IS standard.

If the hosting company utilized App Pools properly then they would not have
to do this.