Its your personal choice. I buy a poppy each year & never collect it, I have a very special poppy (special to me) which I wear each year, so I just give a quid to the British legion in the hope it will help our ex servicemen.
It represents the fallen during WW1, of which there are very few, if any, left, however, the poppy, the "symbol" represents all our war dead, past & present.
To any ex serviceman or woman, wearing one is a mark of respect for our war dead. Its a time to remember the brave souls who gave their lives so we could enjoy our freedom, & our freedom to debate the issue.

.