The day after I turned 70, I got an email urging me to buy burial insurance. “Now more than ever, it’s time to make sure your family is protected,” it said. “You may qualify for amazing rates on burial policies!” I was sure I didn’t qualify because I am not — at least so far — dead. But I began to wonder if reaching a milestone, which is better than having a kidney stone, makes advertisers think you are not long for this world. Even if you are still alive, you may be considered so decrepit that you will need to spend all the money you plan to leave to your family, which in my case would keep t…