We have a duty roster which I draw up monthly. One month I listed one of the elders as "brother," which he was not happy with. Is it really such a violation to call you a brother and not an elder?
Actually, the violation is on the elder's side. Consider that it is said of Jesus, "For both He who sanctifies and those who are sanctified are all from one Father; for which reason He is not ashamed to call them brethren" (Hebrews 2:11). If our God and Savior sees us as brethren, then why does a mere man think he is above his fellow Christians? When Peter was addressing the apostles and elders at the church in Jerusalem, he addressed them and those listening in as "brethren" (Acts 15:6-7, 12).
"Calling them to Himself, Jesus said to them, "You know that those who are recognized as rulers of the Gentiles lord it over them; and their great men exercise authority over them. But it is not this way among you, but whoever wishes to become great among you shall be your servant; and whoever wishes to be first among you shall be slave of all. For even the Son of Man did not come to be served, but to serve, and to give His life a ransom for many"" (Mark 10:42-45).
"Elder" is not a title. It is a job description. We don't make use of titles to make a distinction between members. We call each other brethren to emphasize that we see each other as family and as equals.