It would be worth it if it could keep snails and slugs out of a garden for a season, but if it has to be reapplied often, then it would be to expensive to use.
A 20 lb bag of sluggo cost me $58. I have to put down a teaspoon per square yard every two weeks for at least a year to get any kind of control, not eradication. It needs to be kept up for at least two years without seeing any slugs or snails to call it a cure. It hasn't happened yet. If snails can be eradicated in an area, perimeter treatments need to be continued to keep more from migrating in.
I could get a hen, the feral chickens at the garden keep snail and slug populations down so well that snails are rare. However, chickens will also eat all the seedlings and lettuce and not to mention poop everywhere they go if allowed free range.
Your invention has to be effective have a good cost benefit ratio to be worth the price.
Happy gardening in Hawaii. Gardens are where people grow.