Seriously, is anyone surprised? Yes, he had a great career here - and he was cheered WILDLY during that career. But maybe last night was the first chance fans had to respond to things Peterson did off the field: his departure in the past year and off-field issues and many distractions since 2014. No, I don't want to re-re-re-re-re-re-re-re-debate those, but obviously there are some fans displeased by aspects of his past behavior.
IMO fans booed for an opposing team's player who nearly gained a first down - and was gifted the down on the next no-gain play (were fans actually booing that call?) I'm glad there were fans there to cheer for the Vikings - not for their personal favorite player from the past.