That's very true, although it is so easy to prevent by leaving the Macs with wall and rear mains switches (68030s and older, with what Apple calls 'passive power control', and the CC and other LCs with pseudo-soft or 'active power control') left permanently on.
It is also part of the reason for Apple's use of no rear switch for Macs ever since then, because maintenance of the 5-V TRKL supply for true soft power depends on that continuous connection. It just also happens that the PRAM battery is 'spared' by that continued connection, but only if the connection is maintained.
So easy to do, and 20+ Macs in a room take the edge off the cold, in winter, very well.
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