I think Luton AC rules state specifically that ledgering is not permitted near boats, as a former match angler I had no problem with boats as on the whole it helped the fishing by adding colour to the water. In the winter you'd almost pray for a boat to go through. Anglers prefer you to go down the centre as they usually bait the near and far shelf...If possible run your engine before the match is 'pegged out' and the pegger will not include your mooring in the match. Features like bushes and boats that have been moored for sometime are preffered by matchmen, in fact many go home if they don't draw a peg with a feature that might hold Carp or bream.
I would strongly advise reporting bad behaviour to the local clubs, many let visiting clubs hold matches to help pay for the angling rights and I suspect some of these people are less respectful if they are unfamiliar with canals and boats. The idiots you see by lock moorings are usually kids fishing without a dayticket and probably don't know any better...