Does anyone else have problems with wholesalers who seem to have rather inexplicable gaps in the range of items they carry?

I can understand if a place doesn't deal with specific manufacturers, or slants its stock toward mostly domestic or mostly industrial type items, but I sometimes find it hard to figure out the logic behind why they carry some things but not others, or why they seem to miss silly little things out of their stock.

Taking one supplier (branch near-ish to me in Norwich) as an example:

They carry both 20 and 25mm PVC conduit, with saddles, bends, elbows, the full range of thru, tee, and 4-way boxes, etc., but they don't do a simple 25 x 20mm reducer to allow easy connection of the two sizes.

They carry a fair range of Wylex 3-phase distribution equipment: NH panels, B and C curve MCBs, triple-pole MCBs and isolators, etc. If they are trying to cater for 3-phase commercial installations, why is it then that when you turn to the cable section they stock 6491X (singles for conduit use) only in brown, blue, and green/yellow? Not a reel of black or gray in sight (and it was the same before the color change, just red, black, and green/yellow, no yellow or blue).

The selection of 6491X cable itself is curious. 1.5, 2.5 and 6mm are available in the three essential colors for a single-phase circuit, but when it comes to 4mm they only stock green/yellow. They don't do anything besides green/yellow in 10mm upwards either.

When it comes to switches and sockets, you can select from literally dozens of fancy brass, stainless steel, or other decorative domestic devices. But basic surface-mount metal-clad units for workshop use are in very short supply: Just a few cheapo Powerlectrik types plus an even more restricted range in their own-branded Micromark. Not even anything larger than a 2-gang switch. [Linked Image]

It's not just the lack of range carried, but also the lack of stock of what I would consider to be very basic items in a branch which is supposedly one of the company's "super" warehouses. More than once they've had no stock of 4mm T&E whatsoever. Other times I've ordered a load of PVC conduit fittings only to find that they're down to something like five lengths of 20mm conduit and have only a dozen spacer saddles or four inspection bends in stock. [Linked Image]

They are good on price, but it's annoying to have to go chasing around elsewhere to find all the extras which they either don't carry at all or are out of and "won't have any more for at least a week."