If you need to solve gnarly industrial scale mixed integer combinatorial optimisation problems in the guts of your ML / optimisation engine, the commercial MIP solvers (gurobi , CPLEX ) or non-MIP based alternative combinatorial optimisation systems (localsolver ) can often give more optimal results in exponentially less running time than free open source alternatives.
1% more optimal solutions might translate into 1% more net profit for the entire org if you've gone whole hog and are trying to systematically profit optimise the entire business, so depending on the scale of the org it might be an easy business case to invest a few million dollars to set this system in place.
Annual server licenses for this commerical MIP solver software was 0(100k) / yr per server & the companies that build these products bake a lot of clever tricks from academia into these products that you can exploit by paying the license fee. ( my knowledge of pricing is out of date by about 7 years ) .