A standard problem for retailers is that they cannot determine the willingness to pay of individual consumers. So, in order to price disciminate, they offer different bundles of goods with a pricing schedule that reflects what the retailer thinks is the distribution of consumer types. Here, the high type of consumers (willing to pay a ton for Festool) is separated from the low type (willing to pay a lot but not a ton) by the possibility of buying a more valuable good at a very high price.
If all rails had holes, Festool would be forced to either ignore low types and sell only to high types (high price, fewer sales, lower overall profit) or sell to all types (low price, many sales, lower overall profit). The high types would be happy with the latter since low types would be dictating price, but Festool would not.
Retailers can almost always make more money if they can price discriminate, and this is a great example of this phenomenon. Festool is not a charity, and the option of a rail without holes is not to be nice to consumers. The two rail options allow Festool to charge extra amounts to high type consumers who are willing to pay and therefore extract more money from everyone.
Here is another nice example for you.
When the MFK 700 came out one could only buy the set option (I believe that is what it was called). If I remember correctly, this was the motor, two bases, etc. Then, some months later, a second option came out, one that allowed a purchaser to buy the motor and a single base. Again, my memory may not be perfect on this. Anyway, this order of product introduction was almost certainly not an accident. Festool guesses that there is a set of consumers out there who want the MFK 700 a lot but do not really want the extra base. These are medium types. Along with medium types there are high types who will buy the MFK 700 no matter what. The low types in this situation will not buy an MFK set regardless, that is, they do not want the MFK so much that they will buy it even with the extra base. How to get the medium types to buy the extra base anyway? Have only one bundle when the tool is introduced. Then, after the medium types have bought the MFK 700 but the low types have not, introduce a MFK without the extra base. With this the high types have already bought the set and are pleased, the medium types have bought the set and are pissed because they got stuck with a base they do not want, and finally the low types now buy the MFK without the extra base. Had Festool had the non-extra-base option available from the start, the medium types would have bought it instead of buying the set with the extra base. This would mean less money for Festool.
The right pricing schedule depends on things like the distribution of types, how much they want to pay, etc. All standard pricing theory...
