The Lord's supper should be for all who beleive and have faith in Jesus as our lord and saviour and believe in his sacrifice and ressurection.
The HOW's are very irrelevant, the relevant point is that NO PERSON of faith shoudl be excluded from it.
Whether a group chooses to do it once a year, once a month, once a week or even every time they sit to eat, is irrelevant, what is relevant is that all with faith and belief should partake.