Maybe?
Everywhere I've worked in the US, I always had some level of discretionary spend--even as a lowly summer intern at a behemoth like IBM. It could be software; it could be books; it could be training; it could be computer hardware; it could be lab equipment; it could be groceries or office supplies.
As an intern, I bought some of the first O'Reilly books (mostly about X11) at the Cucumber Book Shop in Bethesda, Maryland courtesy of IBM. As someone way more senior, I once put a T3 line card (about $15K at the time) on my credit card in order to break a budgetary logjam between two feuding departments (and made BOTH of them angry at me--it was beautiful).
Obviously, the more junior I was--the less the value of that spend was. And it went up as I became more senior. And I always had to provide receipts and maybe a bit of justification.
But I've always had some level of discretionary cash spending at even the crappiest companies I've worked for.
Engineers get discretionary spending? I haven't ever had a dollar discretionary. My last job paid for an ergo mouse for me (Logitech Vertical) at hire time and I was so ecstatic at the park and got myself a jumbo mousepad to go with it.
Is there a norm I'm not aware of?