Webber probably thought nothing of hitching a ride on the sidepod of Fernando Alonso's Ferrari at the end of the race in Singapore after the engine in his Red Bull blew on the final lap.
The stewards, however, were left far from impressed upon review of the footage that showed Webber coming close to being run over.
After parking his car down the escape road at turn seven, Webber then jogged to the side of the track and hailed down Alonso, as if calling a taxi.
Alonso, however, stopped in the middle of the track just as the Lotus of Kimi Raikkonen passed to his right, forcing the Finn to also grind to a halt.
Webber then ran to the left-hand side of Alonso's Ferrari and jumped on board, but with Mercedes' Nico Rosberg flashing by directly behind him.
Seconds later a surprised Lewis Hamilton had to slow before taking his own avoiding action by steering to the right of Alonso's car.
Both Webber and Alonso were subsequently reprimanded, but as it was Webber's third of the season, the Australian faces a 10-place grid penalty in Korea under the totting-up procedure.
"Drivers have given others lifts home in previous years - it happened the other way around with Mark and Fernando somewhere else," recalled Horner.
"One of the most iconic images I can remember is of Nigel Mansell giving Ayrton Senna a lift home (1991 British Grand Prix).
"On this occasion it was good for the show, it was good tv, and it should have been dealt with with a fine or a slap on the wrist.
"What's a shame is that it's ended up in a reprimand, and because it's the third it means a 10-place penalty.
"Unfortunately, reprimands are the only things now available to the stewards, and perhaps in this instance talking to the drivers would have sufficed.
"Ideally, a fine would have been better, but I don't think that's something that's available to the stewards now (teams and not drivers can now only be fined).
"It's frustrating because it now puts Mark on the backfoot in Korea, and that's the bit that doesn't really make sense.
"But I understand the difficulty the stewards have with the penalties they have at their disposal."
Hamilton felt Webber was fortunate not to have been run over as he said: "I was doing my in-lap, came round the corner and Fernando was there, and I was really shocked.
"I went to the right, but if Mark had been walking across where I went then I would have run him over.
Fortunately, that wasn't the case.
"In sport, something like that is cool. Remember Nigel Mansell and Ayrton Senna.
"There have been times where I've driven past someone else who has stopped and I'd wished I'd stopped.
"It's good for the fans to see, and as long as it's done in a safe manner, you don't stop on the racing line, then maybe it should be allowed for the future."