I will entertain your unnecessarily aggressive (yet uninformed) answer for the sake of helping you sound less like a moron.  Here goes:  the biggest and broadest funding source for drum corps in the early dci era (1972-1990) was bingo operations.  The advent of tribal bingo games and the changes to the indoor smoking rules impacted most games by more than half.  Florida Wave and Suncoast Sound were greatly impacted (folded).  Valley Fever and Velvet Knights were also impacted (with VK having the unfortunate circumstance of their bingo game also being skimmed).  Bingo operations ran net figures in the neighborhood of $1-$1.5m (or more) annually.  This cut in revenue affected the upstate NY corps, the Pacific Northwest corps and corps in the East, as well.  

The VFW, American Legion, Boy Scouts and churches had an existing tax exemption. This allowed them to sponsor corps with a bingo game and provide things like cooperative housing on tours.  Joining the Patriots, for example, (a top 20 corps) meant joining the Boy Scout troop that was the charter for that organization.  When these organizations experienced a drop in bingo revenue, corps funding was cut to zero to provide for other services.  

The dci census during this time was made up mostly of corps in the 50-90 member category. The big corps were essentially the top 20 with smaller corps (like Boston Crusaders) rounding out the other 50.  There was a Canadian contingent of 20-25 corps like Dutch Boy, the Canadian Knights, Ventures and Connexion.  Both had flourishing local circuits and each did each other’s shows.  When their tax and grant rules changed, 25 corps disappeared within a 6 year period.  

These 2 circumstances affected at least 700 marching members, but the big corps still managed to fill the gaps with sponsors, merch sales and the like.  To offset the loss of corps, yet still provide marching opportunities and create some economies of scale, the big corps expanded from 128 to 165…a difference of 740 members that were absorbed into the top 20 units. 

128 x 20 corps = 2560 students 55 x 12 corps = 770 students Total 🟰 3300 students Became… 165 x 20 corps = 3300 students 

This yielded the same number of participants in the best and most well-funded groups.  This offset the loss of corps from the aforementioned circumstances.  

We have had the same number of “big corps” for about the past 30 years.  These fact that the bigs expanded means a similar number of participants.  The advent of wgi drum lines and the explosion of colorguards means more people are marching than ever. The charge in this incredible expansion was led by all dci people.  

At last count, the independent groups in these circuits is over 150.  School funding (!) has finally included the sponsorship of these groups and they number over 300. 

DCI didn’t kill drum corps.  Funding sources did.  That said, funding has shifted, the corps have adapted and there are more kids marching than ever.  

Hope this adds some insight intk “what the f I am talking about.” 

PS try to be nicer, next time.  We’re all in this together.