Stocks are also traded on many different order books [1], each of which will have different prices, so the quoted price is just as made up (although usually by ignoring all but one venue rather than averaging across them).

Also worth noting that for both stocks and cryptocurrencies, the price that is shown is almost always the last traded price not a quote for a price you could trade at anyway.

[1] in the US, for example: https://www.sec.gov/foia/docs/atslist.htm