A couple points:
1) you don't have to sacrifice any shot. You can concoct a spreader in any payload size that is acceptable for the gauge. You just need to select a starting recipe for a load 1/8 ounce larger than your goal. If you're using 1 ounce regularly and want a 1 ounce spreader, peruse the data for a 1 & 1/8 ounce recipe using your favorite components (you may have to change the wad) and delivering the velocity/pressure you want.
2) you can't have your cake and eat it too. Recognize that a spreader load is not a panacea but actually just a solution to a problem with a fairly narrow set of parameters.
Most patterns are of normal distribution...meaning the pattern density is greater in the center and thins towards the fringes. It's this hot core that allows a cylinder choke to obliterate targets at very close range and actually break some targets with authority at 50 yards.
If I introduce a systematic error that will disrupt the pattern and skew the pellet distribution, like a foreign object in the shot column I can ruin the normal distribution. If I use something that not only disrupts and spreads the hot core, but creates large and unpredictable voids in the pattern, I've ruined it to the point of uselessness.
The goal is to move some of the pellets from the hot core toward the outer edges, thus a) increasing the effective pattern diameter (helping to hit the target) while b) diminishing the likelihood of mangling a centered target. I’m searching here for the mythical “even pattern”, a result often alluded to but virtually nonexistent.
Obviously, (a) is a worthy goal for target shooting...every chipped target is scored an X.
But, (b) is non-essential for target shooting and, IMO, not justification for hunting with spreaders which, I believe, carries too high a risk of crippling game and, worse, injuring a dog.
Back to point (2)....spreaders have a narrower range of effectiveness than a cylinder choke, but within that range they can be even more useful.
As a hypothetical example, assume a cylinder pattern that has optimal spread:density at 20 yds. At 10-15 yds it will obviously have more than adequate density but the spread will be smaller, making it a bit tougher to hit the target. At 25-30 yds the pattern will obviously be wider but thin enough at the edges that the effective pattern is no larger; maybe even smaller but, by virtue of core density, still capable of breaking the target with a well-centered pattern. So, the ideal range of a cylinder choke might cover 15-30 yds.
A well-concocted spreader pattern can be significantly wider than a cylinder pattern at 15 yards and have near-optimum density throughout. But, because of the thinner core density, if it’s optimum at 15 yards it may be inferior at only 25 yards and totally useless at 30 yards.
The only way to know to know a spreader’s performance is to test...your concoction in your gun at your preferred distance. Don’t fall for the casual “ expect one choke difference and only from a tightly choked gun,” or “don’t expect to open to more than IC from a Full choke.” Choke performance has conventionally been discussed as a percentage in a 30” circle at 40 yds. Good enough for mathematical comparisons but wholly irrelevant to real world shooting. It’s absolutely imperative to pattern spreaders at the distance you will shoot, and limit shots to a narrow range or be prepared for disappointment.