So after the fiasco of having to search for a plumbing supply house that carried a PEX compression fitting in the right size for the hot water shut off under the kitchen sink, I should have known better.

But when the hot water shut-off in the downstairs bathroom started leaking, I went to the Big Box stores (plural) and found none of them carry a shut-off valve in the size I need. The largest they have for the incoming supply line is 5/8" diameter, and mine looks to be 3/4".

So, my question: who do I call down vengeance from God upon? My inclination is to blame the Big Box stores for not carrying a proper selection of shut-off valves. Or did the plumber use non-standard sizes when he ran all the water supply lines when the house was built?

Plumbers, weigh in, please!