Often such businesses will use financial instruments to remove risks (and potential rewards) from market fluctuations eg commodity futures, exchange rate swaps, etc.

This reminded me of another example of accidental speculation. An airline used rolling 6 month commercial loans because it was cheaper than long term bonds by a few basis points. This was fine until it wasn’t. Interest rates spiked and the airline was suddenly insolvent.

They’d inadvertently become a speculator on interest rates.

Insurance companies, casinos, stock exchanges, utility companies, universities.

If it were not for government regulation, these companies would have near, infinite riskless profit.