I wear road racing shoes which have some tread. 40% of the race is on tarmac and most of the rest is on fairly solid wet sand. Only one short stretch of soft sand and nothing will give you any grip in that!
Yep, No need for trail shoes........Tactics though......Hard off from the start (uphill) then recover on the road downhill to the beach. Tuck in behind someone tall across the sand then high knee lifts in the water (you will overtake 10s of folk if you can "bound"). A bit of a slog back with wet shoes but dig in as when you hit the road (uphill) most folks die. Leave a bit after the downhill back down to the start for the short, sharp uphill under the railway bridge to the finish. Cross the line down your beer throw up then have a fish supper!!
Don't forget your water wings