By Richard Horgan Los Angeles (Knewz) — With 73 million users across 30 apps, The Dating Group knows single people. In honor of Halloween, the company has cataloged what its users consider “scary” first-date behavior. At the top of the list, for 76 percent of respondents, is someone who checks their phone throughout a first date. That’s enough, they say, for not pursuing any further dates. The next biggest offense, these singles say, is not showing up on time. For 60 percent, that’s a deal breaker as well. And while the people sourced by The Dating Group did not specifically say this was enoug…