I don't think the bookies and owners mind whether you're a seasoned gambler or not. The general public enjoy a flutter too and if there's money to be made then everybody is happy
Who said anything about if the owners mind if you are a seasoned gambler or not? Of course they dont! All they see is the prize money on offer from the sponsors of the race! But at the end of the day the only real winner on Saturday was the bookie, especially when a horse wins with the odds of 33/1. Anyone that backed the favourite (that got killed) was on a hiding to nothing anyway especially with the statistic that no horse since 1934 had won the Cheltenham gold cup and the grand national in the same year and yet the bookie priced the horse with ridicoulsly low odds!
But the grand national imho is not a race of quality these days, and i believe the owners of Synchronized have said they will never have a runner in the race again.