Seventeen players from the breakaway LIV Golf Series will tee up at Wentworth, including Ryder Cup stalwarts Ian Poulter, Lee Westwood and Sergio Garcia.
The US-based PGA Tour has banned those taking part in LIV events but attempts by Europe's DP World Tour to follow suit have been unsuccessful, with LIV players still eligible to compete at its showcase events pending a court hearing next year.
"Even though Lee Westwood and Ian Poulter have been stalwarts for the European Tour, I don't think those guys really should be here," Horschel said.
"Abraham Ancer, Talor Gooch, Jason Kokrak: you've never played this tournament, you've never supported the DP World Tour. Why are you here? You are here for one reason only and that's to try to get world ranking points because you don't have it (via LIV).
"It's pretty hypocritical to come over here and play outside LIV when your big thing was to spend more time with family and want to play less golf."
British Open champion Cameron Smith is the latest marquee name to join the LIV circuit.
