The cost of a call and the cost of a put are almost directly related. If you have a $40 stock, a $40 call and a $40 put will be almost exactly the same price most of the time. If there is a difference, the possibility of an arbitrage usually exists meaning that there is a 0 risk strategy (minus commissions) to get something for nothing. This is true whether it’s a collar or another strategy. I don’t completely understand the full process that allows for that to happen, but a complex series of trades usually makes it possible. So if the price of a call and put are going to be the same that means generally the higher priced calls are due to greater risk. Some reasons may be historical volatility, as that plays a roll, but the implied volatility, that is, how much people expect or are betting on the stock to move, becomes important.