That's interesting. Lucky Bay, yes. and Safety Bay - no problems.
So how did you get around the problem? By heading toward the kiters first?
(Kiter haters don't get excited here)
I had noticed being able to head high upwind when close to the shore but never really thought about why. A bend in the wind. Interesting. Makes sense.
Essentially yes.. you need to bear off a lot more than you think, generally in the direction of the kiters, though maybe not quite that far unless you're doing a speed run

... (but that's getting off topic.. there are other threads that discuss the matters of kites, windsurfers and speed runs)

(back on topic)
When you stand at the beach the wind 'bends' and runs along the shoreline, so it's blowing across the board.. once you get out to the sandbar, you'll probably notice you can start pointing higher on Port tack. That's because the wind swings around behind you.
This is where you mind plays a trick on you.. The wind was coming across the board when you left the shore, so you'd reasonably assume it would be the same case heading back in, but the wind is actually coming across the nose of the board if you're heading in the direction of the carpark area.
So basically in a typical SSW breeze if you're standing on the sandbar and want to head back to the carpark you're going to have to sail pretty close to the wind. Best way I've found is to get your speed up by bearing away, then start driving off the fin, weight forward, back leg straight and get high... I mean go high.
hmm "get high"... perhaps that's what Greenleader, WetWilly and Richiefish are doing? No wind guys?