The PADI guidelines state the 5 OW dives are supposed to be done over 2 days,
Err no. The STANDARDS say "conduct no more than THREE training dives in any one day". They say that clearly. Its a standard not a guideline.
Open Water also only has 4 open water dives which by that standard MUST take 2 days.
but the shop I did them with was willing to do them all in one day, provided I started very early and was willing to stay out on the boat w/o returning, doing generous surface intervals.
So in short the shop you did it with were knowingly and wilfully breaking agency training standards. Name and shame them.