Because doing a setup, which Jono said he'd mostly be using it for [I think], tuning a floater is all about getting it close, then stretching in the strings and start working on getting it closer. Once everything is stretched and you've got it all adjusted back to baseline at correct pitch on all string, you can go ahead and finish with a strobe if you wish. But the act of getting it to that final point in a setup where everything dials in perfect, it's about being close, not pr
écise. You can spend forever being precise when it's going to change the next tuner you touch. It's far easier [for ME] to work with average sensitivity, compared to a strobe. It's not like we're talking about crappy tuners, they're excellent [not good at picking up very low frequencies!!] and I don't need thousandths of a cent, hundredths are plenty accurate for setting up a floater. The only time I need and use the strobe is to set the intonation, which you really only need to do once.
Should you have strobe sensitivity to set the intonation? Yes. But you'll also get several different readings in the many different ways to set intonation.
But for "tuning" a guitar, I'm using my Sabine, Trem or FX.