If I have a net worth of seven figures (excluding IRAs, Home Ownership and 401K) does it still make sense to keep stashing away in the 401K?

In my opinion, yes, it does make sense.

Currently, your net worth is NOT taxed. What is taxed is your annual income. I am assuming that you still get a substantial amountof taxable annual income, either from salary/wages, stock sales, interest earned and other sources.

By putting money away into your 401K, you reduce the tax on that annual income. You will pay the tax when you begin to take distributions from the 401K, but it is likely that your income in those years will not be as high, so the tax burden will be substantially less than the current top rate of 35%.

The assumption of a lower tax bracket in your retirement years is not guaranteed, but it is valid most of the time. If you have the situation where your annual income is still substantial in your retirement years, you can rolled the money from the 401K into a rollover IRA, then contribute to charity directly from the IRA without paying taxes on the proceeds.

Regardless, the historical practice of deferring taxes whenever possible to avoid paying at a currently high marginal tax rate remains the norm in the financial planning field.