that is the logical move for anyone who is not a hardcore trader who cares only about making money. of course there is the buy high sell low situation but that doesn't mean people aren't going to spend 0.001-0.01BTC of what they have.
also and mostly i am talking based on BitPay stats. for example this chart from 2 years ago was the best thing i can show you. it maps number of processed transactions by BitPay (the bars) versus the price (the line). it shows an increase number of them during the ATH of 2013 and a big drop after price came down and then slow growth afterwards
this is the latest stats which is describing the same thing with 328% rise but it doesn't have the same pretty chart!
I suppose another "strategy" by hardcore holders who don't really want to get into the speculation game yet also want to take advantage of high prices, is to spend some Bitcoin when they feel is high, and then save the fiat for buying/replacing that Bitcoin at a lower price. Would help to explain the increased Bitpay transactions (I assume). Or is this also because merchants tend to try Bitpay when price is high, when they know more people are willing to release a finger or two on their Bitcoin holdings?