MAngband

With those spells, priests (and now mages) can get an endless amount of cash. It's too easy to buy 99 plain arrows for a few gold, enchant them to (+9,+9) or brand them into 99 arrows of flame (+2, +3), and then sell them for 10k. Repeat that 100 times and you have 1 million in a few minutes...
In PWMAngband, enchanting or branding via spell puts a 100% off discount on items. I think this should be applied to the main trunk too.

Maybe better solution:

Shop keepers say "i dont want that" always for custom enhanced stuff. All magically enhanced stuff gets bound to the mage and falls apart if dropped.

At lvl 40, if you cannot make 1 million just with regular killing, you're doing something wrong, or have been extremely unlucky with drops. At level 40, you should be down to at least 2500'-3000'. There's alot of cash down there anyway. The monsters practically throw (excellents) after you. And cash won't help you much unless you're extremely lucky in a shop.

ZAL