Many different facets to this discussion.
At its simplest point is the tournament, or club hosted event where host organization has to consider balancing different priorities to make a decision that satisfies different needs (or be totally selfish and serve only theirs). I think that internal debate is rather easy and has a number of answers including full refund, partial refund, no refund, or credit for future event. I'd favor partial refund (to be fair on hosts sunk costs) as future events and teams are uncertain. Very few teams will look the same in August, and for example, most competitive teams at U14 would not play next spring as U15 (as most would be in JV/Varsity ranks as freshmen).
What is much harder is how will clubs react if (when) the season is cancelled. Our leadership team is discussing this right now and making plans, but our financial model is quite simple so relatively easy for us. Mind you, we still have to consider looking after our coaches, staff, and 3rd party vendors to make sure they can survive and are paid fairly for what activities have happened since January, balanced against family or parental expectation that they should get something back (quite reasonably in most cases).
It will be much, much harder for clubs that have all inclusive fees (that include variable costs like leagues, refs and tournaments). Also the more full time staff and coaches to pay, the higher percentage of your budget is tied to salary cost and the human impact to refunds. Those that make hard decisions earlier, will save some of those costs and so naturally should be more inclined to refund the savings.
Seems to me, there should be a correlation here between diminishing spring costs and increasing refund.
What is most important for our club in our discussion is planning for a scenario where our actions in this regard reflects clearly and transparently that any savings we inevitably gain should be returned in some fashion and not added to our margin (typically target 5%) or profit in these sad times. Exactly how much that is, and how we do that is what we need to figure out.
